Battery packs such as NaS batteries, Li-ion batteries, and Ni—H2 batteries configure a battery module by arranging a closely-bundled plurality of individual batteries inside a casing. International Publication No. WO 2012/026224 A1 discloses a rack for battery packs for housing such a battery module. A transportation rack for battery packs disclosed in International Publication No. WO 2012/026224 A1 can be used also as an installation rack, and as such, installation of battery modules can be performed easily.